Key facts
- Brand
- STMicroelectronics
- Model
- ST7FLITEO
- Category
- microcontrollers
- Documents
- 3
- Languages
- EN
- Last added
- 2012-08-07
Start here
STMicroelectronics AN1753 Software UART Using ST7 12-Bit Autoreload Timer
This document details a software implementation of a Universal Asynchronous Receiver/Transmitter (UART) designed for ST7LITEO devices that lack an on-chip SCI peripheral. The solution utilizes the 12-bit autoreload timer and two I/O ports to handle asynchronous receive and transmit operations.
The application supports half-duplex and asynchronous operation with flexible data formats, including 7 or 8 data bits and 1 or 2 stop bits. Supported baud rates range from 2400 to 19200. The note provides configuration instructions for the ST7FLITEO, including clock source setup, input initialization, and timer register configuration, along with a functional software flow and test procedures.
STMicroelectronics ST7FLITEO specifications
| Supported Baud Rate | 2400 to 19200 baud |
|---|---|
| Data Bits | 7 or 8 data bits |
| Stop Bits | 1 or 2 stop bits |
| Operation Mode | Half-duplex |
| Clock Frequency | 8 MHz internal clock |
Source: STMicroelectronics AN1753 Software UART Using ST7 12-Bit Autoreload Timer
All STMicroelectronics ST7FLITEO documents by type
How to use the product for one specific task, with worked examples.
Questions answered in these manuals
What devices is this software UART designed for?
It is designed for devices like the ST7LITEO that have no on-chip SCI peripheral.
From: STMicroelectronics AN1753 Software UART Using ST7 12-Bit Autoreload Timer
What is the program code size?
The program code is 357 bytes.
From: STMicroelectronics AN1753 Software UART Using ST7 12-Bit Autoreload Timer
What are the key advantages of the ST7FLITEO?
The ST7FLITEO is a small low-cost microcontroller that embeds many analog functions, allowing users to save board area and the cost of external components like ceramic resonators and reset circuitry.
Does the ST7FLITEO have an internal oscillator?
Yes, it contains an internal RC oscillator with an accuracy of 1% for a given device, temperature, and voltage, which must be calibrated via software.
What is the purpose of this application note?
The purpose is to present a software solution using the frequency of the European standard mains (220V/50Hz) as a timebase to adjust the internal RC oscillator of the ST7FLITEO to 1 MHz (1%).
From: STMicroelectronics AN1324 ST7FLITEO MCU RC Oscillator Calibration Application Note
How does the calibration software work?
The software uses the mains frequency as a timebase to test if the RC oscillator frequency is above or below 1 MHz and repeatedly transforms it by dichotomous analysis so that in 7 iterations the RCCR is set to the optimum value.
From: STMicroelectronics AN1324 ST7FLITEO MCU RC Oscillator Calibration Application Note